hdu 3172 Virtual Friends

原题链接：http://acm.hdu.edu.cn/showproblem.php?pid=3172 
并查集的运用。。。

 1 #include<algorithm>

 2 #include<iostream>

 3 #include<cstdlib>

 4 #include<cstdio>

 5 #include<map>

 6 using std::map;

 7 using std::string;

 8 const int Max_N = 100010;

 9 struct UnionFind {

10     map<string, int> rec;

11     int num[Max_N], par[Max_N];

12     void init() {

13         for (int i = 1; i < Max_N; i++) {

14             par[i] = i;

15             num[i] = 1;

16         }

17         rec.clear();

18     }

19     inline int find(int x) {

20         while (x != par[x]) {

21             x = par[x] = par[par[x]];

22         }

23         return x;

24     }

25     inline void unite(int x, int y) {

26         x = find(x), y = find(y);

27         if (x != y){

28             par[x] = y;

29             num[y] += num[x];

30             printf("%d\n", num[y]);

31         } else {

32             printf("%d\n", num[y]);

33         }

34     }

35     inline void gogo() {

36         int n, cnt = 1;

37         char s1[100], s2[100];

38         scanf("%d", &n);

39         while (n--) {

40             scanf("%s %s", s1, s2);

41             if (!rec[s1]) rec[s1] = cnt++;

42             if (!rec[s2]) rec[s2] = cnt++;

43             unite(rec[s1], rec[s2]);

44         }

45     }

46 }ans;

47 int main() {

48 #ifdef LOCAL

49     freopen("in.txt", "r", stdin);

50     freopen("out.txt", "w+", stdout);

51 #endif

52     int t;

53     while (~scanf("%d", &t)) {

54         while (t--) ans.init(), ans.gogo();

55     }

56     return 0;

57 }

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